Hi Arvind
Initial stage IBP demand solution could along with SAP APO.
IBP demand could work together with SAP APO DP where you can transfer APO DP data to IBP demand solution for advance features like demand sensing or predictive analysis and get the respective out put back and show in APO DP planning book.
Other IBP solution are complete independent and you require to use them instead of APO.
As you might be knowing in mid-long term, APO solution would be get replaced by IBP solution.
Please go through the following link for more additional information.
http://scn.sap.com/community/scm/ibp
Thanks
Amol